1. Field of the Invention
The present invention relates to an electrical signal connector, and more particularly relates to an electrical signal connector consisting of a locknut, an inner tube, a cylindrical casing, a barrel and a torque sleeve, wherein when a coaxial cable is inserted into the inner tube, the torque sleeve can be moved to force a rear inside bearing surface of the barrel over a first deformable body portion and second deformable body portion of the cylindrical casing, thereby tightening up the engagement between the electrical signal connector and the coaxial cable.
2. Description of the Related Art
With the progress of the times and improvement of the people's living standards, electronic and multimedia technologies have been developing rapidly. In consequence, the sale of TV, stereo, audio and video equipment, digital camera, electronic game machine and many other electronic products keeps growing rapidly every year, and people become more and more critical about the quality of the output signal of entertainment and audio-video equipment. To provide high quality signal output, the quality of related signal line and signal connector is as important as the quality of the entertainment and audio-video equipment itself.
In Community Access Television (CATV) or the so-called cable TV, radio frequency TV signal is transmitted through a fiber optic network and optic nodes to a television of a subscriber via a coaxial cable and related electrical signal connectors and a CATV splitter, providing the subscriber with various services, such as radio and television service, digital television service, on-demand entertainment service, high-speed Internet service, and etc. Different designs and sizes of electrical signal connectors and adapters are commercially available for use with different coaxial cables. To fit different signal transmission quality requirements, the braided outer conductor of a coaxial cable can have a standard, tri-shield or quad-shield design. In consequence, the wire diameter and conductor cutting size must be well controlled to fit the connector so that the impedance between the coaxial cable and the connector can be maintained at 75 Ohm. When a coaxial cable is assembled with an electrical signal connector, a crimping tool may be used to crimp the electrical signal connector, tightening up the engagement between the coaxial cable and the electrical signal connector, avoiding signal loss or permeation of rainwater or impurities.
FIGS. 8 and 9 illustrate an electrical signal connector (cable end connector) A fastened to one end of a coaxial cable B. This cable end connector A consists of a locknut A1, an inner tube A2, a plastic cylindrical casing A3 and a metal barrel A4. The inner tube A2 is fastened to one end of the locknut A1. The plastic cylindrical casing A3 is fastened to the same end of the locknut A1 around the inner tube A2. The metal barrel A4 is movably attached to the distal end of the plastic cylindrical casing A3. During installation, the protective plastic covering B5 of the coaxial cable B is properly stripped off, and then the center conductor B1, insulation spacer B2 and wrapping layer (Mylar film or aluminum foil) B3 of the coaxial cable B are inserted into the plastic cylindrical casing A3 and then the inside space A20 of the inner tube A2 with the braided outer conductor B4 and protective plastic covering B5 of the coaxial cable B attached to the periphery of the plastic cylindrical casing A3. Thereafter, a crimping tool is operated to move the metal barrel A4 relative to the plastic cylindrical casing A3, thereby compressing the plastic cylindrical casing A3 to force internal barbed portions A31 of the plastic cylindrical casing A3 into engagement with the braided outer conductor B4 of the coaxial cable B against the protective plastic covering B5 and the periphery of the inner tube A2. According to this design, the metal barrel A4 is movably attached to the distal end of the plastic cylindrical casing A3 with no guide means provided therebetween. When operating a crimping tool to move the metal barrel A4 relative to the cylindrical casing A3 in forcing the internal barbed portions A31 of the plastic cylindrical casing A3 into engagement with the braided outer conductor B4 of the coaxial cable B, the cylindrical casing A3 may be biased, affecting further signal transmission quality or stability.
To avoid biasing of the cylindrical casing A3 during crimping, an extra accessory may be necessary to guide movement of the metal barrel A4. Further, after insertion of the coaxial cable B into the inside space A20 of the inner tube A2, it is necessary to attach the metal barrel A4 to the distal end of the plastic cylindrical casing A3, complicating the procedure. Further, when moving the metal barrel A4 relative to the plastic cylindrical casing A3 to force the internal barbed portions A31 of the plastic cylindrical casing A3 into engagement with the braided outer conductor B4 of the coaxial cable B, the applied pressure may be not evenly distributed to the coaxial cable B, causing displacement of the coaxial cable B relative to the inner tube A2 and the plastic cylindrical casing 3 and affecting further signal transmission quality or stability.
Therefore, it is desirable to provide an electrical signal connector, which eliminates the drawbacks of the aforesaid prior art design.